Our major goal is the elucidation of the pathophysiology in infants and children with disorders of carbohydrate metabolism, such as hypoglycemia, Glycogen Storage Disease, and Diabetes Mellitus. This should lead to understanding the physiology of carbohydrate regulation and the developmental role of hormones and their receptors in both health and disease. Diet and other treatment modalities will be investigated as well, e.g. long-acting zinc glucagon has been found effective in 1 child with hypoglycemia. Additional studies of erythrocyte insulin receptors have verified their increased numbers in patients with symptomatic hypoglycemia, and following the introduction of nocturnal continuous nasogastric feeding in GSD I. Diazoxide appears to reduce specific I131 insulin binding to red cells. Studies of glycosylated Hbs show significant elevations of the negatively charged minor hemoglobins (HbAI a plus b) in patients with GSD Type I and fructose-diphosphatase deficiency. HbAIc was not changed. Continuous glucose monitoring will be started to better evaluate changes with diet, continuous nasogastric feeds, and tolerance tests in children and adults.